Mill



June 1l, 1940. H w, LANGBE|N Y 2,204,140

` 1' MILL Filed Sept. 28, 193'(` Patented June 11, 194() UNITED STATESv PATENT OFFICE 1 Claim.

This invention relates to a. mill and more particularly pertains to mills of the type employing crushing and grinding rollers and which is applicable for use in reducing solid particles to a iinely comminuted or pulverulent state, and which is also suitable for use in effecting lthe intermixture or inter-grinding of solid particles with liquids or senil-liquids, as in the production of lJastes.

An object of the invention arrangement of the crushing or grinding rollers such that the materials being worked will be subjected successively to a series of grinding and crushing actions and in a manner to effect rapid and thorough 'reduction of the solids being worked and their intermixture with. liquids where the mill is utilized in forming a paste.

` Another object of the invention is to provide a mill of the above character which embodies an effective means for varying the working pressure of the crushing and grinding elements of the mill and which is adapted to be adjusted finely to a predetermined extent. A further object is toprovide a mill with a compression adjustment means adapted to be equipped with an indicator capable of showing the extent of the compression adjustment.

Another object is to provide a construction and arrangement in the crushing and grinding roller assembly whereby the parts embodying the wearing surfaces may be readily removedand replaced.

With the foregoing objects in view, together with such other objects and advantages as may subsequently appear, the invention is carried l into effect as illustrated by way of example in the accompanying drawing in which:

Fig. 1 is a View in vertical section of a mill with parts shown in elevation;

Fig. 2 is a detail in horizontal section taken on the line 2-2 of Fig. 1 showing the manner of forming the roller assembly.

Referring to the drawing more specifically A -indicates generally the base portion `of the mill which may be of any suitable construction but is r here shown as embodying a platform 3 formed with an opening 4 on which platform is seated a hollow base block 5 extending over the opening 4 and on which block is seated and affixed a hollow cylinder 6; the block 5 being formed with an upstanding annular flange I which is encircled by the cylinder 6 andby means of which the cylinder is centered on the block with its inner periphery spaced from and concentric with a circular opening 8 formed in the block 5.

Extending upwardly through the opening 8 and fcc is to provide an revoluble therein is a tubular shaft 9 the lower end of which projects through the opening 4 of the base panel 3 and is fitted with a spur gear I0 engaged by a pinion I0 whereby the shaft 9 may be rotated from any suitable driving mechanism.

The upper portion of the shaft 9 is spaced from the inner peripheryl of the cylinder I5 in concentric relation thereto and interposed bem tween the shaft and cylinder' is a series of superimposed annular rows of grinding and crushing rollers; four of such rows being here shown but which number may manifestly be increased or diminished as occasion may require.

Each row of the rollers embodies a series of concave rollers a. carried in a cage b` and interposed between inner and outer raceways c and d snugly fitted respectively on the outer periphery of the shaft 9 and on the inner periphery of the cylinder 6. As here shown the raceway d of the lowerrnost row of rollers a indicated at II is seated on the flange I with the rollers a bearing on the raceway at an upward and outward incli nation. The inner raceway c of this row II of the rollers bears on the latter and is formed to afford a bearing for the succeeding row of rollers indicated at I2, which latter rollers bear on the upper portion of the double inner raceway c at an upward and inward inclination, thatis, in a direction of incline opposite that of the lower row of rollers II. t

The outer raceway d` of the second row of rollers I2 bears on the latter and seating on this outer raceway and the upper end of its associated inner raceway c is a pair `of spacing rings e and j on which latter is seated the inner race- Way c of the succeeding row I3 of the rollers a the outer raceway d of which seats on the spacing ring e. The rollers a in the row I3 thereof bear on their associated inner raceway c at an upward and inward inclination while the associated raceway d bears on said row of rollers.. Spacing rings g and h, bear respectively on the inner and outer raceways c and d of the row I3 of the rollers, and bearing on the ring g is the inner raceway c of the upper row of rollers I4 against which the rollers a of the latter row bear at an upward and inward inclination. The outer raceway d of the upper row bears on the associated rollers a and also on the spacing ring h.

Owing to the longitudinally concaved character of the individual rollers a, and the correspondingly convexed shapes of the raceway members j c and d which interfit with them, said rollers are maintained in their grinding positions in a very stable manner and also produce a uniform crushing action upon the material being ground.

Seating on the outer raceway d of the upper row of the rollers is a crowding ring i5 the outer periphery of which slidably conforms to the periphery of the upper portion of the cylinder 6 and the inner periphery of which is spaced, outwardly relative to the outer upper margin of the upper inner raceway c to provide a space i for entry of materials to be crushed and ground into the space traversed by the rollers a.

The crowding ring l5 is here shown `as formed on and constituting the lower end of a feed hopper IB, which is formed with an outwardly projectng horizontal flange l@ overlying the upper end of the cylinder 3 and spaced a short distance therefrom.

Mounted on the upper end of the cylinder 6 is an upstanding ring l l formed with an inturned flange ld on its upper margin extending in spaced relation to the flange lil to a point proximate the outer periphery of the 'side wall ls of the hopper E which side wall is circular and tapers downwardly and inwardly in the for n of an inverted truncated cone. Y

interposed between the flanges lil and i3 is a resilient tubular annulus 2U of such cross section as to completely occupy the space bounded by the upper and lower faces respectively of the flanges l5 and lil and by the inner andouter peripheries of the ring il and hopper wall i9 respectively. Connecting with the interior oi the annulus 'isis a conduit 2i leading from any suitable source of supply of huid under pressure and which conduit is fitted with a conventional cuto valve 22 for regulating the delivery of the fluid under pressure to the interior of the annulus 2li to effect expansion of the latter and thereby impart a downward pressure on the flange l5 and its associated crowding ring l5 and thus impose a pressure downwardly on the crushing and grinding roller assemblage.

As a means for enabling the imposing of a predetermined pressure on the roller assemblage the annulus 2li is fitted with a tube 23 leading f from the interior thereof and connecting with a conventional pressure gauge 2t. A

The base block' 5 is formed with a discharge trough which leads downwardly from an opening communicating with the space traversed by thelower row ll of the rollers a, and is fitted with a gate C carried in guides El. The cylinder t -is hollow to provide a water jacket 23 through which water is directed from an intake pipe 29 from any suitablesouroe of supply to ll the water jacket and from which the is passed through the discharge pipes 3l) so as to effect transfer of heat from the crushing and grinding elements operation.

Cooling liquid may also be circulated through a space lll in the base block E and a spray of cooling liquid may be directed into the hollow shaft 9 from the lower end of the latter to effect a cooling action thereon.

ln the operation of the invention the materials to be ground and crushed are fed into the hopper Bin a granular form either in a dry state, or with a liquid when it is desired to effect the grinding action in the presence of liquid. On rotating the shaft il the inner raceways c carried thereon will revolve therewith and accordingly the rotating raoeways c will effect rotation of the rollers o in such manner that the rollers a of the several rows thereof will rotate and .travel collectively in spaced relation to each other on their respective raceways c and d, with the rollers traversing the outer raceway d carried on the xed cylinder 6. The material delivered to the hopper B will feed into the spaces traversed by the upper row lll of rollers a through the space or passage i and will be acted on by these rollers as the materials pass downwardly therebetween; the materials passing successively downward from the row I4 of the rollers through the rows I3, I2 and ll thereof so as to be thereby successively acted upon by the several groups of rollers, The rollers manifestly will act to crush and grind the materials fed thereto and with the result that the materials will be nely pulverized or comminuted when they pass from the lowermost row Il of rollers through the outlet 26 to discharge through the trough 25. The discharge of the ground material is decelerated by reason of the rollers in the lowermost row Il being inclined inwardly as Well as downwardly, thus decreasing the circumference of the annular discharge space between the 'A lowermost raceways c and d.

Any desired pressure may be imposed upon the crushing and grinding rollers by applying fluid under pressure to the interior of the expansible resilient annulus lll which pressure will exert a downward thrust through the crowding ring l5 to the outer raceway d'of the rows of rollers I4, it and l2 respectively, and thereby impart inward and downward pressures on the rollers of these rows and their associated inner raceways c; the downward pressure imposed on the lower double raceway c being directed outwardly and downwardly against the rollers` a of the lower row ll and their associated outer raceway d which is lixedly seated on the base block 5.

Rotation of the shaft S and the raceways c thereon will set up a centrifugal action between the inner and outer raceways tending to throw the materials being worked outwardly which action by reason of the rollers of the three upper rows, i3, lil and l2 thereoi` being inclined outwardly and downwardly with the lower ends of the upper raceway spaced outwardly from the upper end of the succeeding raceway such as to afford inward oil-sets in the passageway through the successive rows ofrollers, will impede the ow oi' the materials downward so as to insure their being subjected to the crushing and grinding action of the rollers. This flow of the materiale is further impeded by inclining the rollers a of the lowermost row inwardly and downwardly.

This arrangement forces the materials tov ow inwardly at vthis point in opposition to centrifugal force thus effecting a sustained action on the materials preliminary to their discharge.

In imposing pressure on the roller assemblage through the medium of the expansible annulus Eli rluid pressure is directed to the interior of the latter from the conduit 2l by vopening the valve 22 until the desired pressure'designated by the pressure gauge 2li is reached, whereupon the valve 22 is closed so as to maintain the roller assembly under the established pressure for such length of time as occasion may require.'

The annulus Eil being resilient is yieldable under excessive upward thrusts as might be imposed thereon through the crowding ring I5 from the roller assembly. v

When it is desired to subject the materials to a more prolonged action of the rollers, the gate C is closed by lowering it in the guides 2l soas to cut off discharge of materials from the mill and accordingly hold the materials in a conlined state within the mill.

It will be manifest that the mill herein set forth is highly suitable for use as a mixer in forming paints and the like, in which the solid materials fed to the mill have been previously ground to requisite neness and require no further grinding action and merely need to be thoroughly inter-mixed with a liquid. In some instances the materials fed to the mill may be in fluid or semi-uid state in which event the roller system will function to effect mixing of the materials Without regard to grinding or crushing action thereon.

While I have shown and described a specific embodiment of my invention I do not limit myself to the exact details of construction and arrangement shown, and it will be understood that various changes and modications may be employed without departing from the spirit of the invention as dened in the accompanying claim.

I claim: In a mill, a series of superimposed rows of crushing and grinding rollers, inner and outer raoeways sup-porting the rollers of each row, means for rotating the inner raceways collectively, a housing slidably supporting the outer-- most raceway, a crowding ring seating on the uppermost outer raceway, a hopper formed on said crowding ring, an outwardly extending flange on said hopper, a confined expansible hollow annulus seating on said ange, and means for directing uid under pressure into said annulus, an increased supply of uid pressure to said annulus causing said crowding ring to press more heavily upon said uppermost outer raceway.

HAROLD W. LANGBEIN. 

